Anytime Tools 5 Diamond Dust Hole Saw for Tile Glass Marble Sizes Included: 1/4", 5/16", 3/8" 1/2", 1" Excellent results in glass, marble, slate, and tile. Segmented design works better and lasts longer. The diamond coating on these saws give superior performance and life. Note: To prolong the life of these bits, use on a low speed with coolant (water/oil)